Conventional hearing aids use a microphone to detect ambient sounds and a loudspeaker or earphone to send sounds into the ear canal to help patients hear when their ears are damaged or otherwise compromised. However, sounds from the loudspeaker or earphone may reach the microphone, causing acoustic feedback issues. Also, such hearing aids direct sounds to the ear through the natural conductive pathway (that is, through the ear drum and to the middle ear bones that vibrate fluids in the cochlea). Consequently, conventional hearing aids are inadequate for certain types of hearing loss caused by physical or genetic ear damage. Moreover, conventional hearing aids or commercial hearing devices suffer from smearing of temporal and spectral information that occurs when amplifying specific frequency bands of sound features to overcome deficits in hearing or for subjects listening in noisy environments interfering with those specific sound features. There are also patients who have tinnitus caused by loss of hearing in certain frequency ranges that can no longer be sufficiently accessed through the normal hearing pathway.
When using hearing aid devices, headphones/earbuds, phones, and other hearing and communication devices in noisy environments, it can be particularly difficult to hear speech sounds. This can occur during conversations in a noisy crowd or room, when someone is using a mobile phone, in a warzone in which soldiers are not able to hear each other during critical military operations, and noisy workplaces in which employees cannot easily communicate with each other to perform their work. Users may wear earplugs to block sounds from entering their ear canals, and some earplugs include speakers for sending to the user desired speech information provided by someone speaking into a phone or microphone device capable of transmitting the speech information wirelessly to the earplug's speakers. However, the ambient noise in the user's environment can still travel through the user's skull/head through bone vibration. Furthermore, those earplugs are not perfect in blocking unwanted sounds and noise, and those earplugs can be quite uncomfortable, especially when worn over a long period of time. The unwanted sound in these different scenarios is thus able to reach the cochlea, masking or otherwise interfering with the speech sounds also reaching the user's cochlea from the hearing or communication device.